The 89 is the same as blackdogjenny's 90 in terms of the reset switch (I presently own an 89 744T and my previous car was a 1991 744T). There is a little rubber stopper in the bottom centre of the speedo, that once you pull out, you can use a pin, nail etc. to press the reset "clock" (and like jenny said, press it firmly). And, yeah, all it means is that the internal clock says it's time for an oil change. It is actually on a timer as opposed to shutting down when operating temp is reached. I think the time is 1.5 or 2 min.

Hope that helps.



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1991 744T 415 000KM sold Sept 2003, Presently: 1989 744T 160000Km